content: /* ===========================================================
   * JFreeChart : a free chart library for the Java(tm) platform
   * ===========================================================
   *
   * (C) Copyright 2000-2012, by Object Refinery Limited and Contributors.
   *
   * Project Info:  http://www.jfree.org/jfreechart/index.html
   *
   * This library is free software; you can redistribute it and/or modify it
   * under the terms of the GNU Lesser General Public License as published by
   * the Free Software Foundation; either version 2.1 of the License, or
   * (at your option) any later version.
   *
   * This library is distributed in the hope that it will be useful, but
   * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
   * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public
   * License for more details.
   *
   * You should have received a copy of the GNU Lesser General Public
   * License along with this library; if not, write to the Free Software
   * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301,
   * USA.
   *
   * [Oracle and Java are registered trademarks of Oracle and/or its affiliates.
   * Other names may be trademarks of their respective owners.]
   *
   * ---------------------------
   * StandardXYItemRenderer.java
   * ---------------------------
   * (C) Copyright 2001-2012, by Object Refinery Limited and Contributors.
   *
   * Original Author:  David Gilbert (for Object Refinery Limited);
   * Contributor(s):   Mark Watson (www.markwatson.com);
   *                   Jonathan Nash;
   *                   Andreas Schneider;
   *                   Norbert Kiesel (for TBD Networks);
   *                   Christian W. Zuckschwerdt;
   *                   Bill Kelemen;
   *                   Nicolas Brodu (for Astrium and EADS Corporate Research
   *                   Center);
   *
   * Changes:
   * --------
   * 19-Oct-2001 : Version 1, based on code by Mark Watson (DG);
   * 22-Oct-2001 : Renamed DataSource.java --> Dataset.java etc. (DG);
   * 21-Dec-2001 : Added working line instance to improve performance (DG);
   * 22-Jan-2002 : Added code to lock crosshairs to data points.  Based on code
   *               by Jonathan Nash (DG);
   * 23-Jan-2002 : Added DrawInfo parameter to drawItem() method (DG);
   * 28-Mar-2002 : Added a property change listener mechanism so that the
   *               renderer no longer needs to be immutable (DG);
   * 02-Apr-2002 : Modified to handle null values (DG);
   * 09-Apr-2002 : Modified draw method to return void.  Removed the translated
   *               zero from the drawItem method.  Override the initialise()
   *               method to calculate it (DG);
   * 13-May-2002 : Added code from Andreas Schneider to allow changing
   *               shapes/colors per item (DG);
   * 24-May-2002 : Incorporated tooltips into chart entities (DG);
   * 25-Jun-2002 : Removed redundant code (DG);
   * 05-Aug-2002 : Incorporated URLs for HTML image maps into chart entities (RA);
   * 08-Aug-2002 : Added discontinuous lines option contributed by
   *               Norbert Kiesel (DG);
   * 20-Aug-2002 : Added user definable default values to be returned by
   *               protected methods unless overridden by a subclass (DG);
   * 23-Sep-2002 : Updated for changes in the XYItemRenderer interface (DG);
   * 02-Oct-2002 : Fixed errors reported by Checkstyle (DG);
   * 25-Mar-2003 : Implemented Serializable (DG);
   * 01-May-2003 : Modified drawItem() method signature (DG);
   * 15-May-2003 : Modified to take into account the plot orientation (DG);
   * 29-Jul-2003 : Amended code that doesn't compile with JDK 1.2.2 (DG);
   * 30-Jul-2003 : Modified entity constructor (CZ);
   * 20-Aug-2003 : Implemented Cloneable and PublicCloneable (DG);
   * 24-Aug-2003 : Added null/NaN checks in drawItem (BK);
   * 08-Sep-2003 : Fixed serialization (NB);
   * 16-Sep-2003 : Changed ChartRenderingInfo --> PlotRenderingInfo (DG);
   * 21-Jan-2004 : Override for getLegendItem() method (DG);
   * 27-Jan-2004 : Moved working line into state object (DG);
   * 10-Feb-2004 : Changed drawItem() method to make cut-and-paste overriding
   *               easier (DG);
   * 25-Feb-2004 : Replaced CrosshairInfo with CrosshairState.  Renamed
   *               XYToolTipGenerator --> XYItemLabelGenerator (DG);
   * 08-Jun-2004 : Modified to use getX() and getY() methods (DG);
   * 15-Jul-2004 : Switched getX() with getXValue() and getY() with
   *               getYValue() (DG);
   * 25-Aug-2004 : Created addEntity() method in superclass (DG);
   * 08-Oct-2004 : Added 'gapThresholdType' as suggested by Mike Watts (DG);
   * 11-Nov-2004 : Now uses ShapeUtilities to translate shapes (DG);
   * 23-Feb-2005 : Fixed getLegendItem() method to show lines.  Fixed bug
   *               1077108 (shape not visible for first item in series) (DG);
   * 10-Apr-2005 : Fixed item label positioning with horizontal orientation (DG);
   * 20-Apr-2005 : Use generators for legend tooltips and URLs (DG);
   * 27-Apr-2005 : Use generator for series label in legend (DG);
   * ------------- JFREECHART 1.0.x ---------------------------------------------
   * 15-Jun-2006 : Fixed bug (1380480) for rendering series as path (DG);
   * 06-Feb-2007 : Fixed bug 1086307, crosshairs with multiple axes (DG);
   * 14-Mar-2007 : Fixed problems with the equals() and clone() methods (DG);
   * 23-Mar-2007 : Clean-up of shapesFilled attributes (DG);
   * 20-Apr-2007 : Updated getLegendItem() and drawItem() for renderer
   *               change (DG);
   * 17-May-2007 : Set datasetIndex and seriesIndex in getLegendItem()
   *               method (DG);
   * 18-May-2007 : Set dataset and seriesKey for LegendItem (DG);
   * 08-Jun-2007 : Fixed bug in entity creation (DG);
   * 21-Nov-2007 : Deprecated override flag methods (DG);
   * 02-Jun-2008 : Fixed tooltips for data items at lower edges of data area (DG);
   * 17-Jun-2008 : Apply legend shape, font and paint attributes (DG);
   *
   */
  
  package org.jfree.chart.renderer.xy;
  
  import java.awt.Graphics2D;
  import java.awt.Image;
  import java.awt.Paint;
  import java.awt.Point;
  import java.awt.Shape;
  import java.awt.Stroke;
  import java.awt.geom.GeneralPath;
  import java.awt.geom.Line2D;
  import java.awt.geom.Rectangle2D;
  import java.io.IOException;
  import java.io.ObjectInputStream;
  import java.io.ObjectOutputStream;
  import java.io.Serializable;
  
  import org.jfree.chart.LegendItem;
  import org.jfree.chart.axis.ValueAxis;
  import org.jfree.chart.ui.RectangleEdge;
  import org.jfree.chart.util.BooleanList;
  import org.jfree.chart.util.PublicCloneable;
  import org.jfree.chart.util.ShapeUtilities;
  import org.jfree.chart.util.UnitType;
  import org.jfree.chart.entity.EntityCollection;
  import org.jfree.chart.event.RendererChangeEvent;
  import org.jfree.chart.labels.XYToolTipGenerator;
  import org.jfree.chart.plot.CrosshairState;
  import org.jfree.chart.plot.Plot;
  import org.jfree.chart.plot.PlotOrientation;
  import org.jfree.chart.plot.PlotRenderingInfo;
  import org.jfree.chart.plot.XYPlot;
  import org.jfree.chart.urls.XYURLGenerator;
  import org.jfree.chart.util.SerialUtilities;
  import org.jfree.data.xy.XYDataset;
  
  /**
   * Standard item renderer for an {@link XYPlot}.  This class can draw (a)
   * shapes at each point, or (b) lines between points, or (c) both shapes and
   * lines.
   * <P>
   * This renderer has been retained for historical reasons and, in general, you
   * should use the {@link XYLineAndShapeRenderer} class instead.
   */
  public class StandardXYItemRenderer extends AbstractXYItemRenderer
          implements XYItemRenderer, Cloneable, PublicCloneable, Serializable {
  
      /** For serialization. */
      private static final long serialVersionUID = -3271351259436865995L;
  
      /** Constant for the type of rendering (shapes only). */
      public static final int SHAPES = 1;
  
      /** Constant for the type of rendering (lines only). */
      public static final int LINES = 2;
  
      /** Constant for the type of rendering (shapes and lines). */
      public static final int SHAPES_AND_LINES = SHAPES | LINES;
  
      /** Constant for the type of rendering (images only). */
      public static final int IMAGES = 4;
  
      /** Constant for the type of rendering (discontinuous lines). */
      public static final int DISCONTINUOUS = 8;
  
      /** Constant for the type of rendering (discontinuous lines). */
      public static final int DISCONTINUOUS_LINES = LINES | DISCONTINUOUS;
  
      /** A flag indicating whether or not shapes are drawn at each XY point. */
      private boolean baseShapesVisible;
  
      /** A flag indicating whether or not lines are drawn between XY points. */
      private boolean plotLines;
  
      /** A flag indicating whether or not images are drawn between XY points. */
      private boolean plotImages;
  
      /** A flag controlling whether or not discontinuous lines are used. */
      private boolean plotDiscontinuous;
  
      /** Specifies how the gap threshold value is interpreted. */
      private UnitType gapThresholdType = UnitType.RELATIVE;
  
      /** Threshold for deciding when to discontinue a line. */
      private double gapThreshold = 1.0;
  
      /**
       * A table of flags that control (per series) whether or not shapes are
       * filled.
       */
      private BooleanList seriesShapesFilled;
  
      /** The default value returned by the getShapeFilled() method. */
      private boolean baseShapesFilled;
  
      /**
       * A flag that controls whether or not each series is drawn as a single
       * path.
       */
      private boolean drawSeriesLineAsPath;
  
      /**
       * The shape that is used to represent a line in the legend.
       * This should never be set to <code>null</code>.
       */
      private transient Shape legendLine;
  
      /**
       * Constructs a new renderer.
       */
      public StandardXYItemRenderer() {
          this(LINES, null);
      }
  
      /**
       * Constructs a new renderer.  To specify the type of renderer, use one of
       * the constants: {@link #SHAPES}, {@link #LINES} or
       * {@link #SHAPES_AND_LINES}.
       *
       * @param type  the type.
       */
      public StandardXYItemRenderer(int type) {
          this(type, null);
      }
  
      /**
       * Constructs a new renderer.  To specify the type of renderer, use one of
       * the constants: {@link #SHAPES}, {@link #LINES} or
       * {@link #SHAPES_AND_LINES}.
       *
       * @param type  the type of renderer.
       * @param toolTipGenerator  the item label generator (<code>null</code>
       *                          permitted).
       */
      public StandardXYItemRenderer(int type,
                                    XYToolTipGenerator toolTipGenerator) {
          this(type, toolTipGenerator, null);
      }
  
      /**
       * Constructs a new renderer.  To specify the type of renderer, use one of
       * the constants: {@link #SHAPES}, {@link #LINES} or
       * {@link #SHAPES_AND_LINES}.
       *
       * @param type  the type of renderer.
       * @param toolTipGenerator  the item label generator (<code>null</code>
       *                          permitted).
       * @param urlGenerator  the URL generator.
       */
      public StandardXYItemRenderer(int type,
                                    XYToolTipGenerator toolTipGenerator,
                                    XYURLGenerator urlGenerator) {
  
          super();
          setDefaultToolTipGenerator(toolTipGenerator);
          setURLGenerator(urlGenerator);
          if ((type & SHAPES) != 0) {
              this.baseShapesVisible = true;
          }
          if ((type & LINES) != 0) {
              this.plotLines = true;
          }
          if ((type & IMAGES) != 0) {
              this.plotImages = true;
          }
          if ((type & DISCONTINUOUS) != 0) {
              this.plotDiscontinuous = true;
          }
  
          this.seriesShapesFilled = new BooleanList();
          this.baseShapesFilled = true;
          this.legendLine = new Line2D.Double(-7.0, 0.0, 7.0, 0.0);
          this.drawSeriesLineAsPath = false;
      }
  
      /**
       * Returns true if shapes are being plotted by the renderer.
       *
       * @return <code>true</code> if shapes are being plotted by the renderer.
       *
       * @see #setBaseShapesVisible
       */
      public boolean getBaseShapesVisible() {
          return this.baseShapesVisible;
      }
  
      /**
       * Sets the flag that controls whether or not a shape is plotted at each
       * data point.
       *
       * @param flag  the flag.
       *
       * @see #getBaseShapesVisible
       */
      public void setBaseShapesVisible(boolean flag) {
          if (this.baseShapesVisible != flag) {
              this.baseShapesVisible = flag;
              fireChangeEvent();
          }
      }
  
      // SHAPES FILLED
  
      /**
       * Returns the flag used to control whether or not the shape for an item is
       * filled.
       * <p>
       * The default implementation passes control to the
       * <code>getSeriesShapesFilled</code> method.  You can override this method
       * if you require different behaviour.
       *
       * @param series  the series index (zero-based).
       * @param item  the item index (zero-based).
       *
       * @return A boolean.
       *
       * @see #getSeriesShapesFilled(int)
       */
      public boolean getItemShapeFilled(int series, int item) {
          Boolean flag = this.seriesShapesFilled.getBoolean(series);
          if (flag != null) {
              return flag;
          }
          else {
              return this.baseShapesFilled;
          }
      }
  
      /**
       * Returns the flag used to control whether or not the shapes for a series
       * are filled.
       *
       * @param series  the series index (zero-based).
       *
       * @return A boolean.
       */
      public Boolean getSeriesShapesFilled(int series) {
          return this.seriesShapesFilled.getBoolean(series);
      }
  
      /**
       * Sets the 'shapes filled' flag for a series and sends a
       * {@link RendererChangeEvent} to all registered listeners.
       *
       * @param series  the series index (zero-based).
       * @param flag  the flag.
       *
       * @see #getSeriesShapesFilled(int)
       */
      public void setSeriesShapesFilled(int series, Boolean flag) {
          this.seriesShapesFilled.setBoolean(series, flag);
          fireChangeEvent();
      }
  
      /**
       * Returns the base 'shape filled' attribute.
       *
       * @return The base flag.
       *
       * @see #setBaseShapesFilled(boolean)
       */
      public boolean getBaseShapesFilled() {
          return this.baseShapesFilled;
      }
  
      /**
       * Sets the base 'shapes filled' flag and sends a
       * {@link RendererChangeEvent} to all registered listeners.
       *
       * @param flag  the flag.
       *
       * @see #getBaseShapesFilled()
       */
      public void setBaseShapesFilled(boolean flag) {
          this.baseShapesFilled = flag;
      }
  
      /**
       * Returns true if lines are being plotted by the renderer.
       *
       * @return <code>true</code> if lines are being plotted by the renderer.
       *
       * @see #setPlotLines(boolean)
       */
      public boolean getPlotLines() {
          return this.plotLines;
      }
  
      /**
       * Sets the flag that controls whether or not a line is plotted between
       * each data point and sends a {@link RendererChangeEvent} to all
       * registered listeners.
       *
       * @param flag  the flag.
       *
       * @see #getPlotLines()
       */
      public void setPlotLines(boolean flag) {
          if (this.plotLines != flag) {
              this.plotLines = flag;
              fireChangeEvent();
          }
      }
  
      /**
       * Returns the gap threshold type (relative or absolute).
       *
       * @return The type.
       *
       * @see #setGapThresholdType(UnitType)
       */
      public UnitType getGapThresholdType() {
          return this.gapThresholdType;
      }
  
      /**
       * Sets the gap threshold type and sends a {@link RendererChangeEvent} to
       * all registered listeners.
       *
       * @param thresholdType  the type (<code>null</code> not permitted).
       *
       * @see #getGapThresholdType()
       */
      public void setGapThresholdType(UnitType thresholdType) {
          if (thresholdType == null) {
              throw new IllegalArgumentException(
                      "Null 'thresholdType' argument.");
          }
          this.gapThresholdType = thresholdType;
          fireChangeEvent();
      }
  
      /**
       * Returns the gap threshold for discontinuous lines.
       *
       * @return The gap threshold.
       *
       * @see #setGapThreshold(double)
       */
      public double getGapThreshold() {
          return this.gapThreshold;
      }
  
      /**
       * Sets the gap threshold for discontinuous lines and sends a
       * {@link RendererChangeEvent} to all registered listeners.
       *
       * @param t  the threshold.
       *
       * @see #getGapThreshold()
       */
      public void setGapThreshold(double t) {
          this.gapThreshold = t;
          fireChangeEvent();
      }
  
      /**
       * Returns true if images are being plotted by the renderer.
       *
       * @return <code>true</code> if images are being plotted by the renderer.
       *
       * @see #setPlotImages(boolean)
       */
      public boolean getPlotImages() {
          return this.plotImages;
      }
  
      /**
       * Sets the flag that controls whether or not an image is drawn at each
       * data point and sends a {@link RendererChangeEvent} to all registered
       * listeners.
       *
       * @param flag  the flag.
       *
       * @see #getPlotImages()
       */
      public void setPlotImages(boolean flag) {
          if (this.plotImages != flag) {
              this.plotImages = flag;
              fireChangeEvent();
          }
      }
  
      /**
       * Returns a flag that controls whether or not the renderer shows
       * discontinuous lines.
       *
       * @return <code>true</code> if lines should be discontinuous.
       */
      public boolean getPlotDiscontinuous() {
          return this.plotDiscontinuous;
      }
  
      /**
       * Sets the flag that controls whether or not the renderer shows
       * discontinuous lines, and sends a {@link RendererChangeEvent} to all
       * registered listeners.
       *
       * @param flag  the new flag value.
       *
       * @since 1.0.5
       */
      public void setPlotDiscontinuous(boolean flag) {
          if (this.plotDiscontinuous != flag) {
              this.plotDiscontinuous = flag;
              fireChangeEvent();
          }
      }
  
      /**
       * Returns a flag that controls whether or not each series is drawn as a
       * single path.
       *
       * @return A boolean.
       *
       * @see #setDrawSeriesLineAsPath(boolean)
       */
      public boolean getDrawSeriesLineAsPath() {
          return this.drawSeriesLineAsPath;
      }
  
      /**
       * Sets the flag that controls whether or not each series is drawn as a
       * single path.
       *
       * @param flag  the flag.
       *
       * @see #getDrawSeriesLineAsPath()
       */
      public void setDrawSeriesLineAsPath(boolean flag) {
          this.drawSeriesLineAsPath = flag;
      }
  
      /**
       * Returns the shape used to represent a line in the legend.
       *
       * @return The legend line (never <code>null</code>).
       *
       * @see #setLegendLine(Shape)
       */
      public Shape getLegendLine() {
          return this.legendLine;
      }
  
      /**
       * Sets the shape used as a line in each legend item and sends a
       * {@link RendererChangeEvent} to all registered listeners.
       *
       * @param line  the line (<code>null</code> not permitted).
       *
       * @see #getLegendLine()
       */
      public void setLegendLine(Shape line) {
          if (line == null) {
              throw new IllegalArgumentException("Null 'line' argument.");
          }
          this.legendLine = line;
          fireChangeEvent();
      }
  
      /**
       * Returns a legend item for a series.
       *
       * @param datasetIndex  the dataset index (zero-based).
       * @param series  the series index (zero-based).
       *
       * @return A legend item for the series.
       */
      @Override
      public LegendItem getLegendItem(int datasetIndex, int series) {
          XYPlot plot = getPlot();
          if (plot == null) {
              return null;
          }
          LegendItem result = null;
          XYDataset dataset = plot.getDataset(datasetIndex);
          if (dataset != null) {
              if (getItemVisible(series, 0)) {
                  String label = getLegendItemLabelGenerator().generateLabel(
                          dataset, series);
                  String description = label;
                  String toolTipText = null;
                  if (getLegendItemToolTipGenerator() != null) {
                      toolTipText = getLegendItemToolTipGenerator().generateLabel(
                              dataset, series);
                  }
                  String urlText = null;
                  if (getLegendItemURLGenerator() != null) {
                      urlText = getLegendItemURLGenerator().generateLabel(
                              dataset, series);
                  }
                  Shape shape = lookupLegendShape(series);
                  boolean shapeFilled = getItemShapeFilled(series, 0);
                  Paint paint = lookupSeriesPaint(series);
                  Paint linePaint = paint;
                  Stroke lineStroke = lookupSeriesStroke(series);
                  result = new LegendItem(label, description, toolTipText,
                          urlText, this.baseShapesVisible, shape, shapeFilled,
                          paint, !shapeFilled, paint, lineStroke,
                          this.plotLines, this.legendLine, lineStroke, linePaint);
                  result.setLabelFont(lookupLegendTextFont(series));
                  Paint labelPaint = lookupLegendTextPaint(series);
                  if (labelPaint != null) {
                      result.setLabelPaint(labelPaint);
                  }
                  result.setDataset(dataset);
                  result.setDatasetIndex(datasetIndex);
                  result.setSeriesKey(dataset.getSeriesKey(series));
                  result.setSeriesIndex(series);
              }
          }
          return result;
      }
  
      /**
       * Records the state for the renderer.  This is used to preserve state
       * information between calls to the drawItem() method for a single chart
       * drawing.
       */
      public static class State extends XYItemRendererState {
  
          /** The path for the current series. */
          public GeneralPath seriesPath;
  
          /** The series index. */
          private int seriesIndex;
  
          /**
           * A flag that indicates if the last (x, y) point was 'good'
           * (non-null).
           */
          private boolean lastPointGood;
  
          /**
           * Creates a new state instance.
           *
           * @param info  the plot rendering info.
           */
          public State(PlotRenderingInfo info) {
              super(info);
          }
  
          /**
           * Returns a flag that indicates if the last point drawn (in the
           * current series) was 'good' (non-null).
           *
           * @return A boolean.
           */
          public boolean isLastPointGood() {
              return this.lastPointGood;
          }
  
          /**
           * Sets a flag that indicates if the last point drawn (in the current
           * series) was 'good' (non-null).
           *
           * @param good  the flag.
           */
          public void setLastPointGood(boolean good) {
              this.lastPointGood = good;
          }
  
          /**
           * Returns the series index for the current path.
           *
           * @return The series index for the current path.
           */
          public int getSeriesIndex() {
              return this.seriesIndex;
          }
  
          /**
           * Sets the series index for the current path.
           *
           * @param index  the index.
           */
          public void setSeriesIndex(int index) {
              this.seriesIndex = index;
          }
      }
  
      /**
       * Initialises the renderer.
       * <P>
       * This method will be called before the first item is rendered, giving the
       * renderer an opportunity to initialise any state information it wants to
       * maintain. The renderer can do nothing if it chooses.
       *
       * @param g2  the graphics device.
       * @param dataArea  the area inside the axes.
       * @param plot  the plot.
       * @param data  the data.
       * @param info  an optional info collection object to return data back to
       *              the caller.
       *
       * @return The renderer state.
       */
      @Override
      public XYItemRendererState initialise(Graphics2D g2,
                                            Rectangle2D dataArea,
                                            XYPlot plot,
                                            XYDataset data,
                                            PlotRenderingInfo info) {
  
          State state = new State(info);
          state.seriesPath = new GeneralPath();
          state.seriesIndex = -1;
          return state;
  
      }
  
      /**
       * Draws the visual representation of a single data item.
       *
       * @param g2  the graphics device.
       * @param state  the renderer state.
       * @param dataArea  the area within which the data is being drawn.
       * @param info  collects information about the drawing.
       * @param plot  the plot (can be used to obtain standard color information
       *              etc).
       * @param domainAxis  the domain axis.
       * @param rangeAxis  the range axis.
       * @param dataset  the dataset.
       * @param series  the series index (zero-based).
       * @param item  the item index (zero-based).
       * @param crosshairState  crosshair information for the plot
       *                        (<code>null</code> permitted).
       * @param pass  the pass index.
       */
      @Override
      public void drawItem(Graphics2D g2,
                           XYItemRendererState state,
                           Rectangle2D dataArea,
                           PlotRenderingInfo info,
                           XYPlot plot,
                           ValueAxis domainAxis,
                           ValueAxis rangeAxis,
                           XYDataset dataset,
                           int series,
                           int item,
                           CrosshairState crosshairState,
                           int pass) {
  
          boolean itemVisible = getItemVisible(series, item);
  
          // setup for collecting optional entity info...
          Shape entityArea = null;
          EntityCollection entities = null;
          if (info != null) {
              entities = info.getOwner().getEntityCollection();
          }
  
          PlotOrientation orientation = plot.getOrientation();
          Paint paint = getItemPaint(series, item);
          Stroke seriesStroke = getItemStroke(series, item);
          g2.setPaint(paint);
          g2.setStroke(seriesStroke);
  
          // get the data point...
          double x1 = dataset.getXValue(series, item);
          double y1 = dataset.getYValue(series, item);
          if (Double.isNaN(x1) || Double.isNaN(y1)) {
              itemVisible = false;
          }
  
          RectangleEdge xAxisLocation = plot.getDomainAxisEdge();
          RectangleEdge yAxisLocation = plot.getRangeAxisEdge();
          double transX1 = domainAxis.valueToJava2D(x1, dataArea, xAxisLocation);
          double transY1 = rangeAxis.valueToJava2D(y1, dataArea, yAxisLocation);
  
          if (getPlotLines()) {
              if (this.drawSeriesLineAsPath) {
                  State s = (State) state;
                  if (s.getSeriesIndex() != series) {
                      // we are starting a new series path
                      s.seriesPath.reset();
                      s.lastPointGood = false;
                      s.setSeriesIndex(series);
                  }
  
                  // update path to reflect latest point
                  if (itemVisible && !Double.isNaN(transX1)
                          && !Double.isNaN(transY1)) {
                      float x = (float) transX1;
                      float y = (float) transY1;
                      if (orientation == PlotOrientation.HORIZONTAL) {
                          x = (float) transY1;
                          y = (float) transX1;
                      }
                      if (s.isLastPointGood()) {
                          // TODO: check threshold
                          s.seriesPath.lineTo(x, y);
                      }
                      else {
                          s.seriesPath.moveTo(x, y);
                      }
                      s.setLastPointGood(true);
                  }
                  else {
                      s.setLastPointGood(false);
                  }
                  if (item == dataset.getItemCount(series) - 1) {
                      if (s.seriesIndex == series) {
                          // draw path
                          g2.setStroke(lookupSeriesStroke(series));
                          g2.setPaint(lookupSeriesPaint(series));
                          g2.draw(s.seriesPath);
                      }
                  }
              }
  
              else if (item != 0 && itemVisible) {
                  // get the previous data point...
                  double x0 = dataset.getXValue(series, item - 1);
                  double y0 = dataset.getYValue(series, item - 1);
                  if (!Double.isNaN(x0) && !Double.isNaN(y0)) {
                      boolean drawLine = true;
                      if (getPlotDiscontinuous()) {
                          // only draw a line if the gap between the current and
                          // previous data point is within the threshold
                          int numX = dataset.getItemCount(series);
                          double minX = dataset.getXValue(series, 0);
                          double maxX = dataset.getXValue(series, numX - 1);
                          if (this.gapThresholdType == UnitType.ABSOLUTE) {
                              drawLine = Math.abs(x1 - x0) <= this.gapThreshold;
                          }
                          else {
                              drawLine = Math.abs(x1 - x0) <= ((maxX - minX)
                                  / numX * getGapThreshold());
                          }
                      }
                      if (drawLine) {
                          double transX0 = domainAxis.valueToJava2D(x0, dataArea,
                                  xAxisLocation);
                          double transY0 = rangeAxis.valueToJava2D(y0, dataArea,
                                  yAxisLocation);
  
                          // only draw if we have good values
                          if (Double.isNaN(transX0) || Double.isNaN(transY0)
                              || Double.isNaN(transX1) || Double.isNaN(transY1)) {
                              return;
                          }
  
                          if (orientation == PlotOrientation.HORIZONTAL) {
                              state.workingLine.setLine(transY0, transX0,
                                      transY1, transX1);
                          }
                          else if (orientation == PlotOrientation.VERTICAL) {
                              state.workingLine.setLine(transX0, transY0,
                                      transX1, transY1);
                          }
  
                          if (state.workingLine.intersects(dataArea)) {
                              g2.draw(state.workingLine);
                          }
                      }
                  }
              }
          }
  
          // we needed to get this far even for invisible items, to ensure that
          // seriesPath updates happened, but now there is nothing more we need
          // to do for non-visible items...
          if (!itemVisible) {
              return;
          }
  
          if (getBaseShapesVisible()) {
  
              Shape shape = getItemShape(series, item);
              if (orientation == PlotOrientation.HORIZONTAL) {
                  shape = ShapeUtilities.createTranslatedShape(shape, transY1,
                          transX1);
              }
              else if (orientation == PlotOrientation.VERTICAL) {
                  shape = ShapeUtilities.createTranslatedShape(shape, transX1,
                          transY1);
              }
              if (shape.intersects(dataArea)) {
                  if (getItemShapeFilled(series, item)) {
                      g2.fill(shape);
                  }
                  else {
                      g2.draw(shape);
                  }
              }
              entityArea = shape;
  
          }
  
          if (getPlotImages()) {
              Image image = getImage(plot, series, item, transX1, transY1);
              if (image != null) {
                  Point hotspot = getImageHotspot(plot, series, item, transX1,
                          transY1, image);
                  g2.drawImage(image, (int) (transX1 - hotspot.getX()),
                          (int) (transY1 - hotspot.getY()), null);
                  entityArea = new Rectangle2D.Double(transX1 - hotspot.getX(),
                          transY1 - hotspot.getY(), image.getWidth(null),
                          image.getHeight(null));
              }
  
          }
  
          double xx = transX1;
          double yy = transY1;
          if (orientation == PlotOrientation.HORIZONTAL) {
              xx = transY1;
              yy = transX1;
          }
  
          // draw the item label if there is one...
          if (isItemLabelVisible(series, item)) {
              drawItemLabel(g2, orientation, dataset, series, item, xx, yy,
                      (y1 < 0.0));
          }
  
          int domainAxisIndex = plot.getDomainAxisIndex(domainAxis);
          int rangeAxisIndex = plot.getRangeAxisIndex(rangeAxis);
          updateCrosshairValues(crosshairState, x1, y1, domainAxisIndex,
                  rangeAxisIndex, transX1, transY1, orientation);
  
          // add an entity for the item...
          if (entities != null && isPointInRect(dataArea, xx, yy)) {
              addEntity(entities, entityArea, dataset, series, item, xx, yy);
          }
  
      }
  
      /**
       * Tests this renderer for equality with another object.
       *
       * @param obj  the object (<code>null</code> permitted).
       *
       * @return A boolean.
       */
      @Override
      public boolean equals(Object obj) {
  
          if (obj == this) {
              return true;
          }
          if (!(obj instanceof StandardXYItemRenderer)) {
              return false;
          }
          StandardXYItemRenderer that = (StandardXYItemRenderer) obj;
          if (this.baseShapesVisible != that.baseShapesVisible) {
              return false;
          }
          if (this.plotLines != that.plotLines) {
              return false;
          }
          if (this.plotImages != that.plotImages) {
              return false;
          }
          if (this.plotDiscontinuous != that.plotDiscontinuous) {
              return false;
          }
          if (this.gapThresholdType != that.gapThresholdType) {
              return false;
          }
          if (this.gapThreshold != that.gapThreshold) {
              return false;
          }
          if (!this.seriesShapesFilled.equals(that.seriesShapesFilled)) {
              return false;
          }
          if (this.baseShapesFilled != that.baseShapesFilled) {
              return false;
          }
          if (this.drawSeriesLineAsPath != that.drawSeriesLineAsPath) {
              return false;
          }
          if (!ShapeUtilities.equal(this.legendLine, that.legendLine)) {
              return false;
          }
          return super.equals(obj);
  
      }
  
      /**
       * Returns a clone of the renderer.
       *
       * @return A clone.
       *
       * @throws CloneNotSupportedException  if the renderer cannot be cloned.
       */
      @Override
      public Object clone() throws CloneNotSupportedException {
          StandardXYItemRenderer clone = (StandardXYItemRenderer) super.clone();
          clone.seriesShapesFilled
                  = (BooleanList) this.seriesShapesFilled.clone();
          clone.legendLine = ShapeUtilities.clone(this.legendLine);
          return clone;
      }
  
      ////////////////////////////////////////////////////////////////////////////
      // PROTECTED METHODS
      // These provide the opportunity to subclass the standard renderer and
      // create custom effects.
      ////////////////////////////////////////////////////////////////////////////
  
      /**
       * Returns the image used to draw a single data item.
       *
       * @param plot  the plot (can be used to obtain standard color information
       *              etc).
       * @param series  the series index.
       * @param item  the item index.
       * @param x  the x value of the item.
       * @param y  the y value of the item.
       *
       * @return The image.
       *
       * @see #getPlotImages()
       */
      protected Image getImage(Plot plot, int series, int item,
                               double x, double y) {
          // this method must be overridden if you want to display images
          return null;
      }
  
      /**
       * Returns the hotspot of the image used to draw a single data item.
       * The hotspot is the point relative to the top left of the image
       * that should indicate the data item. The default is the center of the
       * image.
       *
       * @param plot  the plot (can be used to obtain standard color information
       *              etc).
       * @param image  the image (can be used to get size information about the
       *               image)
       * @param series  the series index
       * @param item  the item index
       * @param x  the x value of the item
       * @param y  the y value of the item
       *
       * @return The hotspot used to draw the data item.
       */
      protected Point getImageHotspot(Plot plot, int series, int item,
                                      double x, double y, Image image) {
  
          int height = image.getHeight(null);
          int width = image.getWidth(null);
          return new Point(width / 2, height / 2);
  
      }
  
      /**
       * Provides serialization support.
       *
       * @param stream  the input stream.
       *
       * @throws IOException  if there is an I/O error.
       * @throws ClassNotFoundException  if there is a classpath problem.
       */
      private void readObject(ObjectInputStream stream)
              throws IOException, ClassNotFoundException {
          stream.defaultReadObject();
          this.legendLine = SerialUtilities.readShape(stream);
      }
  
      /**
       * Provides serialization support.
       *
       * @param stream  the output stream.
       *
       * @throws IOException  if there is an I/O error.
       */
      private void writeObject(ObjectOutputStream stream) throws IOException {
          stream.defaultWriteObject();
          SerialUtilities.writeShape(this.legendLine, stream);
      }
  
  }
  